1. Field of the Invention
The present invention relates to a continuous swimming apparatus wherein the swimmer remains stationary with respect to the apparatus while water in the tank circulates past the swimmer.
2. Description of the Related Art
Continuous swimming tanks are known generally. German Patent No. 2,222,594-Hoppe shows a continuous swimming tank. In the tank described therein, water circulates from the front of a swimming area past the swimmer to the rear of the swimming area where it is recalculated through a duct which runs beneath the floor of the swimming area. One set of turning vanes directs the water from the swimming area to the recirculation duct. The water passes over a propeller located in the duct and used for circulation. The second set of turning vanes directs the water from the recirculation duct back into the front of the swimming area.
The swimming area shown in the German '594 patent widens from the front of the tank to the rear of the tank. That is, the cross-sectional area of the swimming area increases from the front to the rear of the tank. This results in velocity variations over the length of the tank. The velocity of the flowing water is greater at the front of the swimming area than it is at the rear of the swimming area. Thus, a swimmer may choose where to swim, according to water velocity. The flow rate of water is constant anywhere in a given cross-section, perpendicular to the direction of water flow.
The problem with such a design is that it requires a large swimming area and thus a large swimming tank. Further, a large motor and great deal of power is required to circulate such a large volume of water.
U.S. Pat. No. 2,035,835--Raber shows a continuous swimming tank. In this reference, water is circulated either beneath the floor of the swimming area or around the sides of the swimming area. No turning vanes are used to direct the water. The problem with such a tank is that large amounts of turbulence are developed, and loss of water velocity results. Therefore, more power is needed to circulate the water, and swimming comfort is adversely affected by the turbulence.